An Eco-Friendly Management of Pulse Beetle, Callosobruchus chinensis using Neem Formulations in Black Gram

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1 An Eco-Friendly Management of Pulse Beetle, Callosobruchus chinensis using Neem Formulations in Black Gram Rajasri M 1, Sudharani M 2, Rao P S 3 Seed Research & Technology Centre; Acharya N.G.Ranga Agricultural University, Rajendranagar, Hyderabad, India Abstract: The efficacy of different neem products like neem seed powder, neem cake, neem dry leaf powder, neem oil and commercially available neem formulations viz., Econeem plus, Neemindia and Neemazal were evaluated in the laboratory for the control of pulse beetle, C. chinensis in stored black gram. The black gram seed was treated with the neem products were stored under ambient conditions and the data was recorded at three months interval on germinability, seedling vigour index and insect damage. All the neem formulations were found to be effective against C. chinensis in stored black gram up to 15 months of storage. Neem 5 ml/kg seed affected badly the germinability and seedling vigour of black gram seed under storage. The neem formulations viz., Neemazal, Econeem plus and neem cake were on par with deltamethrin found to be very effective against pulse beetle and improved the storability and quality of black gram seed. These neem products are safe, cheap, residue free and eco-friendly seed protectants that can fit into the IPM package of stored grain pests of black gram. Keywords: Blackgram, Callosobruchus chinensis, germination, neem formulations, seedling vigour, storage pests 1. Introduction Black gram (Vigna mungo) is an important pulse crop in Inida and is the main source of protein for the predominantly vegetarian population of country. It is also a rich source of energy, minerals, vitamins and plays a major role in correcting malnutrition. The pulse beetle, Callosobruchus chinensis Linn (Coleoptera, Bruchidae) is one of the most destructive pests infesting stored pulses in India. Due to short life cycle and high degree of reproductive capacity, losses caused by this beetle to the pulses have been estimated to the tune of 30-40% in storage [12]. Hence, the management of pulse beetle is vital for successful and long term storage of the pulses. At present, the pest control measures in storage rely on the use of synthetic insecticides, however their injudicious and repeated use have created several problems such as insect resistance and toxic residues in food grains. The growing awareness of hazards of excessive use of pesticides globally had led researchers for safer and more environment friendly alternatives for pest control under storage. One of such methods is the use of plant products to protect the stored grains, as these are cheap, easily available, target specific and safe to environment and human beings. In view of this, the present studies were undertaken to evaluate the insecticidal efficacy of certain commercially available neem formulations against pulse beetle as an alternative to chemical control in stored black gram. 2. Materials and Methods available neem formulations viz., Econeem plus (Margo Bio-Controls Private Ltd., Bangalore, India) Neemindia (ITC Ltd., India) and Neemazal (EID Parry India Limited ) were tested against pulse beetle in black gram seed. 40 mg/kg seed was used as standard chemical check for comparison. One kg of freshly harvested certified seed with high germination (> 90%) and low moisture content (10%) was used for experimentation. Required quantity of neem formulation was added and mixed thoroughly for proper coating on the seed. The seeds were packed in gunny bags of 2 kg capacity and kept in laboratory under ambient conditions of 27±5 0 C temperature and 65±5% RH. The data recording was initiated after three months of storage and continued up to 18 months of storage at three months interval. Observations on oviposition of pulse beetle, adult emergence, seed germination, seedling vigour index and pulse beetle damage were recorded. To test the viability of seed, germination test using paper towel technique was carried out as per the procedure given by [7]. Germinated seeds were counted on 10 th day and ten germinated seedlings were selected from each replication of the treatment for calculating the seedling vigor index. The shoot and root length of each of the ten seedlings were measured in centimeters and total length of the seedling was calculated. The seedling vigor index was calculated by using the following formulas [1]. Seedling vigour index (SVI) = Germination (%) x Total seedling length (cm).the data were statistically analyzed using MSTAT statistical package. 3. Results and Discussion Laboratory and storage studies were conducted at Seed Entomology Laboratory, Seed Research and Technology Centre, Acharya N G Ranga Agricultural University, Hyderabad, India. Untreated, freshly harvested, insect free and clean black gram seed with little dockage was used for experimental purpose. Four indigenously available neem products viz., neem seed kernel powder, neem cake, neem dry leaf powder and crude neem oil and three commercially The pooled results of the two years were combined and presented as detailed below. Effect of neem formulations on oviposition of C. chinensis: Significant reduction in egg laying was observed in all the neem formulations treated seeds compared to the untreated control (Fig.1). Among the seven treatments, Neemazal, Econeem plus and neem seed kernel powder were found to Paper ID: OCT

2 be superior with no egg laying on treated seeds compared to untreated control where a mean number of 135 eggs were deposited for 50 seeds. Figure 1: Effect of neem formulations on oviposition of pulse beetle on treated black gram seed Figure 2: Effect of neem formulations on adult emergence of pulse beetle in black gram The reduced oviposition rate due to neem formulations was also reported by many workers. [14] observed that ovicidal and oviposition inhibition properties of neem oil. Similarly, [10] and [11] reported a significant reduction in egg laying and adult emergence in C. maculatus treated with neem seed oil. [18] reported that the neem oil (5 ml/kg) was most effective as oviposition deterrent and also increased the developmental period resulting in minimum growth indices of the C. chinensis. Effect of neem formulations on pulse beetle emergence: The mean number of adults emerged was significantly less with all the neem treatments (16 to 58 insects) compared to control (241 insects / kg seed) as indicated in (Fig.2). Neemazal recorded lowest number of adult emergence (16 Paper ID: OCT

3 insects) followed by Econeem plus, neem cake (20 insects) and found superior to chemical check deltamethrin (22 insects). Neem oil treatment also reduced oviposition, inhibited adult emergence and development of C. maculatus, C. chinensis and C. analis [21], [17], [2]. [15] found that neem oil did not allow adult emergence along with reduced oviposition and also prevented insect development against pulse beetle attack in Vigna radiata. Effect of neem formulations on pulse beetle damage: The per cent damage in black gram seeds treated with different neem formulations at different storage intervals was found to be significant (Table 1 and Fig.3). All the neem products provided excellent control over pulse beetle damage with no insect infestation on par with deltamethrin up to 12 months of storage as against 10.5 % insect damage recorded with untreated control. Fifteen months after storage, Neemazal, NSK powder and neem cake proved to be superior seed protectants with no insect damage followed by Econeem plus and neem-india (< 1%) compared to high insect damage of 22.2% in untreated control. Neemazal protected the black gram seed against C. chinensis damage (1.26 %) better than the local neem products, which in turn provided far better protection against the pulse beetle compared to 37.21% in untreated control up to 18 months in stored black gram. The overall mean insect damage indicated that Neemazal, Econeem plus, Neemcake and neem oil proved to be better protectants of stored black gram seed (< 1%) and on par with deltamethrin (0%) compared to untreated control (12.1%). The present research findings are in agreement with the earlier researchers who have reported the efficacy of neem products on pulse beetle damage in stored pulses [21], [17], [3]. Table 1: Effect of neem formulations on pulse beetle incidence in black gram during storage Months after storage Treatments Insect damage (%) * Mean NSK powder 0 0(0.7) 0(0.7) 0(0.7) 0(0.7) 15.2(22.9) 2.5(8.9) Neem cake 0 0(0.7) 0(0.7) 0(0.7) 0 (0.7) 3.92( 11.4) 0.7(4.7) Neem dry leaf powder 0 0(0.7) 0(0.7) 0(0.7) 14.2(22.1) 26.6( 31.0) 6.8(15.0) Neem oil 0 0(0.7) 0(0.7) 0(0.7) 2.59(8.7) 2.92( 9.7) 0.9(4.5) Neemindia 0 0(0.7) 0(0.7) 0(0.7) 1.1(5.4) 6.74( 15.0) 1.3(6.1) Econeem plus 0 0(0.7) 0(0.7) 0(0.7) 0.9(1.8) 3.68( 10.9) 0.8(4.3) Neemazal 0 0(0.7) 0(0.7) 0(0.7) 0 (0.7) 1.26( 6.4) 0.2(2.1) Deltamethrin 0 0(0.7) 0(0.7) 0(0.7) 0 (0.7) 0.0 (0.7) 0.0(0.7) Control 0 1.0(4.6 )4.5( 12.4)10.5(18.9 ) 22.2(28.1) 37.21( 37.6) 12.1( 20.3) 5% NS *Figures in parentheses are arcsine transformed values Figure 3: Effect of neem formulations on the pulse beetle damage of black gram seed at different storage intervals Paper ID: OCT

4 Table 2: Effect of neem formulations on the germinability and seedling vigour index of black gram during storage Months after storage Treatments Germination (%)* Seedling vigor index ** Mean Mean NSK powder g/kg seed ( 75.3) ( 73.9) (73.2 ) (72.8 ) ( 70.3) (60.5 ) (66.8) (45.8 ) (41.6 ) ( 40.4) ( 37.8) (33.5 ) (30.3 ) (38.6) Neem cake g/kg seed ( 75.0) (70.08 ) (69.05 ) (67.2 ) (67.2 ) (65.5 ) (67.6) (47.4 ) ( 43.9) (41.6 ) (39.8 ) ( 34.9) (31.2 ) (40.2) Neem leaf powder ( 72.5) ( 69.05) ( 61.0) ( 61.2) ( 58.9) ( 57.2) ( 46.4) ( 42.4) ( 40.6) ( 30.9) ( 30.5) ( 29.2) (62.4) 5g/kg seed Neem oil ml/kg seed (51.8 ) ( 50.85) ( 49.7) ( 49.1) (49.1 ) (48.8 ) (49.8) ( 42.6) (41.8 ) (34.6 ) (33.3 ) ( 26.7) ( 24.0) (34.5) Neemindia ml/kg seed ( 76.3) ( 75.0) ( 71.7) ( 69.9) (62.5 ) ( 59.4) (61.2) ( 43.3) Econeem plus ml/kg seed (75.6 ) (74.5 ) ( 74.1) ( 71.6) (71.3 ) (63.9 ) (67.8) ( 46.0) Neemazal ( 75.2) ( 75.0) ( 75.0) ( 75.0) (75.0 ) (74.8 ) ( 47.7) (75.0) seed 40 mg /kg seed 92.0 (76.1 ) Control 89.3 ( 73.0) 90.0 ( 75.0) 83.0 ( 66.3) 89.0 ( 74.5) ( 61.4) 88.6 ( 74.2) 69.0 ( 56.4) ( 73.7) (52.0 ) 86.3 (69.4 ) 50.0 (45.0 ) 88.9 (74.5) 73.2 (58.8) 2275 ( 47.7) 1796 ( 42.3) ( 41.8) 1752 (41.8 ) 1808 ( 42.4) 2167 ( 46.5) 1714 (41.4 ) ( 33.9) 1727 (41.5 ) 1760 ( 41.9) 1663 ( 40.7) 1615 (40.19) (31.9 ) 1218 (34.8 ) 1279 ( 35.6) 1252 ( 35.3) 1256 ( 35.4) ( 30.9) ( 29.3) (30.4 ) ( 29.8) (35.7 ) ( 31.6) (33.4 ) ( 31.2) (33.1 ) ( 30.3) 5% * Figures in parenthesis are arcsine transformed values ** Figures in parenthesis are square root transformed values Effect of neem formulations on seed germination and seedling vigour: Among the different neem formulations, seeds treated with Neemazal registered highest seed germination (90%) up to 15 months of storage of black gram seed (Table 2.). Except crude neem oil, all other neem products maintained germinability of black gram seed above seed certification standards (>80%) upto six months of storage but the germination of neem oil treated seeds was dropped to 61.6 % within three months of storage which is less than the germination of untreated seeds (89.3%).The pooled mean data of 18 months of storage indicated that neem formulations viz., Neemazal (90%), Econeem plus (85.7%), neem cake (85.5%) and NSK powder (84.5%) recorded high germination and on par with chemical check deltamethrin (88.9%) compared to low germination recorded with crude neem oil (58.4%) and untreated check (73.2%). Hence, commercial neem formulation, Neemazal was proved superior to the local neem products in grain protection against germination loss and on par with chemical check deltamethrin, with crude neem oil being the least effective (58%). Similar reports of reduced germination of pulse seeds due to neem oil treatment was reported by [20]. In contrary, [13] in green gram and [19] in cow pea reported that neem oil at 0.5 % maintained higher germination and seed vigour during storage. The studies on seedling vigour index of black gram seed at different storage intervals indicated that the vigour of seedlings decreased with the increase of storage period. The pooled mean data of 18 months of seed storage indicated significant differences in seedling vigour index of treated seeds at different storage intervals (Table 2). Neem cake, Neemazal followed by Econeem plus proved superior to all other neem formulations with highest seedling vigour (1616, 1566 and 1439, respectively) throughout the storage period of 18 months compared to chemical check deltamethrin Paper ID: OCT (35.6) 1439 (37.9) 1566 (39.5) 1573 (39.6) 1399 (37.3) (1578) and untreated control (1399). Crude neem oil treatment to black gram seed resulted in not only poor germination but also less vigour of the seedling. Toxicity of neem based formulations have also been reported elsewhere [16], [6], [9], [4], [8]. The present results receive support from [5] who reported that Neemazal-W (a powder formulation) gave mortality and reduction in progeny of five major pests of stored grains including T. castaneum. The results of present study emphasized the potential of indigenous and biological neem based products like Neem cake, NSK powder and commercially available neem formulations like Neemazal and Econeem plus in the storage of pulses and can be used as alternatives to conventional insecticides like deltamethrin for long term safe storage of pulses. These neem products are safe, cheap, residue free and eco-friendly materials that can fit into the IPM package of stored grain pests of pulses. 4. Acknowledgements The authors gratefully acknowledge the help of Dr. S.N. Sinha, Principal Investigator (Seed Entomology) and Dr. Asit B. Mandal, Project Director, D.S.R, Mau, I.C.A.R for funding this research work. References [1] Abdul-Baki AA and Anderson JD. (1973). Vigor determination in soybean seeds by multiplecriteria. Crop Science, 13: [2] Babu TR, Reddy VS and Hussaini SH. (1989). Effect of edible and non edible oils on the development of the

5 pulse beetle, Callosobruchus chinensis (L.) and on viability and yield of mungbean (Vigna radiata (L.) Wilczek). Tropical Science. 29: [3] Das GP and Karim MA. (1986). Effectiveness of some seed kernel oils as surface protectants against pulse beetle, Callosobruchus chinenesis Linn.(Bruchidae: Coleoptera). Tropical grain legume Bulletin. 33: [4] Das DR, Parween S and Faruki SI. (2006). Efficacy of commercial neem-based insecticide, Nimbicidine against eggs of the red flour beetle Tribolium castaneum (Herbst). University Journal of Zoology. Rajshahi University 25: [5] EI-Lakwah FA and EI-Kashlan IH. (1999). Efficacy of Neemazal (powder 10%) against some stored product insects. Alexandria Journal of Agricultural Research. 44(2): [6] Hou XW, Fields PG and Taylor W. (2004). The effect of repellent on penetration into packaging by stored product insects. Journal of Stored Product Research.40(1): [7] ISTA (1999). International rules for seed testing. Seed Science and Technology, Supplement Rules 27: [8] Khalequzzaman M and Khanom M. (2006). Effects of cypermethrin alone and in combination with leaf and seed extracts of neem against adult Tribolium castaneum (Herbst). University Journal of Zoology. Rajshahi University 25: [9] Koul O. (2004). Biological activity of volatile Di-n- Propyl Disulfide from seeds of neem, Azadirachta indica (Meliaceae), to two species of stored grain pests, Sitophilus oryzae (L.) and Tribolium castaneum (Herbst). Journal of Economic Entomology. 97(3): [10] Lale NES and Abdulrahman HT. (1999). Evaluation of neem (Azadirachta indica A. juss) Seed oil obtained by different methods and neem powder for the management of Callosobruchus maculatus (F.) (Coleoptera: Bruchidae) in stored cowpea. Journal of stored Product Research. 35: [11] Lale NES and Mustapha A. (2000). Potential of combining neem (Azadirachta indica A. juss) seed oil with varietal resistance for the management of the cowpea bruchid,callosobruchus maculatus (F.). Journal of Stored Product Research. 36: [12] Mahendran K and Mohan S. (2002). Technology adoption, estimation of loss and farmers behavior in pulses storage A study in Western Tamil Nadu. Pestology. 26: [13] Patil AD and Tandale MB. (1999). Efficacy of plant products against pulse beetle. Thesis Abstract. 26 (4) : [14] Pereira J. (1983). The effectiveness of six vegetable oils as protectants of cowpeas and bombara groundnuts against infestation by Callosobruchus maculates (F). (Coleoptera: Bruchidae). Journal of stored products Research. 19(2) : [15] Ratnasekera D and Rajapakse RHS. (2009). Repellent properties of plant oil vapours on Pulse beetle (Callosobruchus maculatus.) (Coleoptera: Bruchidae) in stored green gram (Vigna radiata). Tropical Agricultural Research and Extension 12: [16] Sahayaraj K and Paulraj MG. (2000). Impact of some plant products on the behaviour of Tribolium castaneum in groundnut seed. International Arachis Newsletter. 20: [17] Sujatha A and Punnaiah KC. (1985). Effect of coating stored seeds of green gram with vegetable oils on the development of pulse beetle. Indian Journal of Agricultural Sciences. 55: [18] Satya Vir. (1994). Effectiveness of natural oils in protection of cowpea seeds from bean weevil, Callasobruchus maculatus Fab. Bulletin of Grain Technology. 32: [19] Sreeramaiah and Bommegouda A. (1992). Studies on the effect of containers and seed Treatments on the storability of cowpea (Vigna unguiculata (L.) Walp.). Seed Tech News. 22: [20] Vijayalakshmi K and Goswami BK. (1986). Effect of seed treatments with neem cake and neem oil on the germination of moong(green gram) and its vulnerability to root-knot nematode. International nematology network newsletter.3: 8-9. [21] Yadav TD. (1985). Anti ovipositional and ovicidal toxicity of neem (Azadirachta indica A. Juss) oil against three species of Callosobruchus. Neem Newsletter. 2: 5-6. Paper ID: OCT